Refrigerating apparatus



Sept., 30, w24.`

D. F. KEITH REFRIGERATING APPARATUS Filed April l2, 1923 5 Sheets-$heet 2 Sept. 30, 1924. 1,510,147

D. F. KEITH REFRIGERAT ING APPARATUS Filed April l2, 1923 5 Sheets-Sheet 3 *L ATTORNEYS Sept. 30. 1924. K l",51,l47

D. F. KEITH REFR IGERAT ING APPARATUS Filed April 12 1923 BY l ATTORNEYS Sept. 30 1924.

f 1,510,147 EL F.| E|Tr1 REFRIGERATING APPARATUS Filed Apil 12. 1923 5 snets-sheet 5 J a r kr ---6 ATTORNEYS Patented Sept. 3o, 1924,

UNITED STATES PATENT OFFICE.

REFRIGERATING APPARATUS.

Application led April 12, 1923-. Serial No. 631,527.

T o all whom it may concern:

Be it known that DAVID Fonns KEITH, a subject of the King of Great Britain, residing at rToronto, in the county of York and 5. Province of Ontario, Canada, has invented new and useful Improvements in Refrigerating Apparatus, of which the following is a specification.

This invention relates to refrigerating apparatus of the intermittent-absorption type and more particularly to simple refrigerating apparatus which may be used in the home.

In refrigerating apparatus of this type,

a refrigerant solution contained within a generator-absorber tank is heated to generate refrigerant gas which passes through a circulation system to a condenser-evaporator tank where the gas is liquefied owing to internal pressure and to the application of cooling means to the condenser. When a -predetermined amount of liquid refrigerant has accumulated in the condenser-evaporator. the heating of the generator-absorber discontinued. Cooling means are then applied to the generator-absorber to lower its internal pressure, causing the revaporization of the refrigerant liquid accumu: lated in the condenser-evaporator, and the reabsorption of this vapor in the liquid remaining in the generator absorber, the latent heat of such revaporization being abstracted from the air within a cold orstorage chamber which is further chilled in consequence. v

An important object of the invention is to produce a simple improved refrigerating apparatus of the intermittent-absorption type which is entirelyT automatic in operation and in which heat is directly removed from the cold chamber by the vaporization of the refrigerant contained within the condenserevaporator situated within said chamber.

A further object of thepinvention is to provide means for rendering inoperative the heating means aforesaid in case the supply of cooling means (such as water) falls below a predetermined safe quantity, or temperature.

i A further object of the invention is to provide distributing means for the cooling means arranged to normally supply the cooling means either to the generator-absorber or the condenser-evaporator in accordance and cooling of the condenser-evaporator are with the point which has been reached in the operating cycle, but which will supply the cooling means to the generator-absorber alone in case the supply of cooling means falls below the aforesaid safe limit.

A further object is to provide in a refrigerating apparatuCl of the type described improved means to prevent a dangerous increase of pressure within the apparatus.

Still another object of the invention is to provide, in a refrigerating apparatus having a circulation system for the refrigerant, an improved gravity-operated valve to alternately open and close a portion of said system to control the circulation therein.

Still another object of the invention is to provide a refrigerating apparatus which may be constructed, and supplied with refrigerating fluid, ready for use, at the factory, and may then, without special attention, be safely shipped to its ultimate destination where it can be quickly connected for operation by any mechanic, the parts being so arranged that inversion or shaking of the apparatus in shipping will produce no harmful eHects.

Another obj ect of the invention is to provide in a refrigerating apparatus of the ty e described, improved means for arresting t e cycle of operation while the temperature of the cold chamber is below a predetermined value, and to associate therewith means to produce blocks of ice of a size convenient to ,use in drinking glasses for example.

Another object of the invention is to provide an improved safety-device for service with closed vessels such as employed in refrigerating apparatus containing fluid under abnormal pressure, which safety-device will blow out when the pressure within the vessel exceeds a definite predetermined safelimit and will carry off the contents of the vessel in such a way as to avoid`undesirable effects attending such blow-out.

Various other objects will be pointed out or become apparent as the description progresses.

The invention comprises in its preferred embodiment a generator-absorber and a condenser-evaporator mounted on opposite arms of a rocking-frame, which passes through an aperture in the heat-insulating wall of a cold chamber, the condenser-evaporator being located within said chamber, mean-s actuated in response to the rocking of said frame in one direction for commencing the refrigerating cycle .of operation, and means controlled by the temperature of said cold chamber and evaporator for preventing such movement of said frame while said temperature is below a predetermined ligure.

A preferred embodiment of the invention further comprises the employment of a 'float maintained at a more orless constant level by the local accumulation of a supply of cooling medium, such as water, so long asy such supply does not fall below a predetermined level in its container, and arranged in case of falling below such level to cut oil the supply of electricity or other power from the heating means aforesaid.

The invention will be more readily understood from a consideration of the accompanying drawings which illustrate one embodiment thereof, and in which- -Figure 1 is a front sectional elevation, with certain parts broken away, of the refrigerating apparatus in the position occupied during the generation of the refrigcrant gas;

Fig. 2 is a diagrammatic front elevation, similar to Fig. 1, showing the apparatus in the position occupied during the absorption of the refrigerant gas;

Fig. 3 is a sectional plan View taken on the line 3-3 of Fig. 2;

Fi 4 is a sectional end View taken on the lme 4--4 of Fig. l;

Fig. 5 is a vertical section taken on the line 5-5 of Fig. 6, showing one structure for regulating the supply of cooling medium and for disconnecting the heating means upon decrease of the local accumulation of such medium below a safe quantity;

Fig. 6 is a horizontal section taken on the line 6-6 of Fig. 5;

Fig. 7 is aplan viewof one means for distributing the cooling medium;

Fig. 8 is a vertical section taken on the line 8-8 of Fig. 7;

Fig. 9 is a section through the evaporator chamber, parts being omitted;

Fig. 1() is a lon 'tudinal section of a safety-blow out; an Fig. 11 is a section of a detail.

In these drawings, 1 designates the outside wall olf a cabinet which is divided by the walls 2, of heat-insulating material, into a chamber 3 for the evaporator and an ap-` paratus chamber 4. A metallic drip pan 5 rests on the floor of the apparatus chamber and is provided with a low vertical wall 6 from which there arise on the side adjacent the chamber 3 two spaced uprights 7 preferably cast integral with the drip pan. Supported on the uprights 7 and secured thereto as by cap screws 8 is a casting 9 having a central upwardly eX- tending annular portion 10. The uprights 7 are bored to receive a horizontal shaft up of two main members 12 and 12b insulated from one another by a bakelte washer 12, and clamped together by a bolt y12d which is insulated fromthe part 12a by a bushing 12". The part 12a is provided with arms 13, while the part 12b is provided with an arm 14. Lugs 15 are used to support the part 12a from the shaft 11. Movement of the rocking-frame to the left is limited by the abutment of its upright portion against a washer 16 adjustably held by nuts 17 onla bolt 18 which is threaded through the lower central portion of casting 9. To the outer ends of the left-hand arms 13 of the rocking-frame there is scoured a generator-absorber 19, here shown as a drum- The right-hand arm 14 of the rocking-frame is in the form of a flanged conduit and supports a condenser-evaporator 20. Movement of the rocking-frame 12 to raise the generator-absorber and lower the condenser-evaporator is limited by abutment of the margins of the Washer 12C against the annular portion 10 of casting 9, in which position the passage between working chamber 4 and chamber 3 is tightly closed while the top of the condenser evaporator slopes very gently to the right (away from the fulcrum-shaft 11).

The condenser-evaporator, while essentially but a closed container, most desirably takes the form oil a number of approximately horizontally disposed metal tubes 22 closed at their inner ends which are welded to a trough 23 carried by the right-hand arm 14 of the rocking-frame. The `condenser-evaporator is further secured to said rocking-frame between upper and lower flanged portions 211 of said arm. The tubes 22 of the condenser-evaporator are in contact throughout their length and are covered by a thin protective coating 25 of suitable heat-conducting material such as zinc which may be applied as by galvanizing and insures the water-tightness oil the channels between said tubes. The outer ends of the tubes discharged into a closed header 2G,

`. the rearwardly sloping bottom 27 of which collects any liquid within the header at its left-hand rear corner to which is connected a return pipe 28.

Referring now to the circulation of the cooling medium, herein described as water, there is provided a pipe 29 passing downwardly through the cover of the cabinet and terminating in a substantially horizontal end to direct a stream of water into a trough 30 which is supported by pipes 31 and 32 to move with the rocking-frame. While supply pipe 29 may be connected to any convenient exterior supply of water, 1t most desirably receives water from an open tank 33 which is here shown as seated on llO the top of the cabinet and shown in detail in Figs. 5 and 6. The boX 33 encloses a Water-tight container 34 which is supplied with water through a pipe 35 connected to a water main. The water pressure applied to`\pipe 29 is maintained substantially constant by a suitable valve 36, the movable cone .37 of which is operated by a float 38 hinged 4to pipe 29 at 39, as seenin Fig.5. Float 38 comprises a water-tight float having a depression 40 in its upper surface to hold a non-conducting cup 41 Whichcarries a small quantity of mercury 42. In the normal operation of the water circulating system, there is a constant flow of water through pipe 35 linto container 34 which maintains the level of water in said container at. aconstant height, thereby lifting float 38 to a point which just permits water to pass through valve 36" at a rate equal tothe outiow through pipe 29 to the refrigerating apparatus. If for any reason the level of the locally accumulated water in container 34 should'raise above its nor- I mal height, it would be carried away through a large drain pipe 43, thus preventing accidental overflow of the container. If the supply of water coming in through pipe 35 falls below the necessary rate to maintain the proper level of water in container 34, ball float 38g is lowered carrying with it its mercury cup 41 and t ereby in-v terrupting the source of power for the refrigerating apparatus in a manner to be described; The Hoat 38 may be provided with a fusible plug 38 of paraflin which will meltin case the water supply becomes too warm. The float will then fill and drop so as to interrupt the above-mentioned source of ower.

uring the generation ofy refrigerant vapor when the apparatus is in the position shown in Fig. 1, and, while the water in container 34 is at' its -normal level, pipe 29 will deliver a stream of water indicated by dotted lines 44 in Fig. 8, and by the small arrows in Fig. 1, which stream falls into the ri ht-hand compartment of trou 'h 30 forme by a low vertical wall 45 whic separa-tes the trough into right and left-hand compartments. If, however, the water-pressure should fall so as to decrease below a safe minimumthe quantity of cooling water supplied, pipe 29 would allo-W the water to trickle down, as indicated by dotted lines 46 againstfthe sloping rear wall 47 of trough 3 0, so that, as seen in Fig. i', upon the occurrence of this condition the water will pass through the lefthand compartment of the trough into pipe 32 regardless of the position of the rocking-frame.

Assumin the water supply to be normal and the'roc ing-frame to be in' its left-hand positin, as indicated in Fig. 1, the cooling water flows through pipe 31 into a closed 'reservoir 48 secured to upper iange 24 of the right-hand arm 14 of the rocking-trame. Reservoir 48 discharges the cooling water through a number ot' pipes 49 upon the ridges of alternate tubes 22 of the condenser-evaporator so that the stream from each pipe 49 is divided and runs down the depressions on either side of the tube 22 which it strikes to cool the contents of the condenser-evaporator. As seen in Fig. 3, the depressions between the tubes discharge into trough 23 whence the cooling water is collected in conduit 14, whence the water iows into a drain conduit 50 and through a water jacket 51 drained by a pipe 52 which discharges the water into a sump 53 located in drip pan 5. The water level in sump 53 is maintained constant by an overflow. pipe 54 which discharges into any convenient drain not shown.

When the. apparatus is in the position shown in Fig. 2, water flows from the pipe 29 into the left-hand compartment of trough 30 and through pipe 32 into contact with generator-absorber drum 19 to cool the same. As here shown, there is provided a wat/er jacket 55 to hold the cooling water in contact with the cylindrical surface of the drum 19, but such a water jacket is not essential since pipe 32 might be arranged merely to spray the water so that it would flow over the upper portion of drum 19 and be collected in the drip pan 5. Where awater jacket is provided, it is drained through a pipe 56 into sump 53, thereby maintaining the portion of drip pan 5 outside the sump normally dry.

Referrin neXt to the heat-supplying system, there 1s associated with the generatorabsorbe-r 19 a source of heat of any known or suitable type, but herein described as an electric stove and conventionally indi-A lcated bythe dotted circle 57 in Fig. 2, which is supplied with electric power through two terminals 58 at the front end of drum 19 which are bent downwardly so as to venter freely intothe. openings in the top of two cups 59. The cups 59 are supported on a block 60 of suitable insulating material which is secured to a flange-61 of wall 6 of the drip pan. Two conductors 62 and 63 forming an insulated cable 64 leading to the terminal box may be connected to the cups 59 as by the binding screws indicated. When drum 19 is in its lowermost position (as in Fig. 1),/the' ends of terminals 58 enter mercury contained in the cups 59, thereby closing the circuit of the electric stove 57 to heat the solution contained within the tank. When the apparatus is in the position shown in Fig. 2, however, the terminals 58 are removed from the mercury and the circuit of the stove is broken. The circuit of the stove will also be broken in case the supply of cooling water to tank 33 becomes too warm or falls below a safe minimum. l I

As seen in Fig. 6, power is supplied to the stove by connecting the free ends of conductors 62 and 6? to any suitable source of power not shown. The circuit may be traced y from one pole of the source ofy power, end

of conductor63, upper metal bracket 65 and a rod 66 depending therefrom through the mercury 42 contained in the float valve cup 41, thence through a' second metal rod 66 and its supporting bracket 65 through cable the circuit just traced, it will be obvious that a sufficient fall in the level of water in container 34 will lower float 38 to withdraw the mercury 42 from contact with rods 66, thereby positively disconnecting all power from thel refrigerating apparatus. The rods l 66 are adjustably secured in their brackets 65 so that the point at which such discon nection will occur may be regulated in accordance with the particular conditions of operation encountered.

From the foregoing, it is obvious that in order' tb., discontinue refrigeration it is merely necessary to shut off the supply of water to' pipe 35 by-any suitable valve not shown. It is manifest that, instead of resting the tank 33 upon the cover of cabinet 1, it could be located within the cabinet so long as there is suiiicient water above the upper end of pipe 29 to maintain the necessary pressure` to produce jet 44 previously described. Moreover, instead ofkemploying the mercury switch described as carried by Hoat 38, it is obvious that a laminated metallic switch could be employed, one member thereof being carried by float 38 to interconnect 'two members`carried by brackets 65. Again, instead of using the electric switch described to control the connections to the stove, the vertical movement of float 38 due to changes in the level of water in cony such as aqua-ammonia within the generatorabsorber is heated to generate refrigerant vapor (ammonia gas when ammonia is the refrigerant used) which is conducted to the condenser-evaporator where it is cooled and condensed. When substantially all the refrigerant gas has been driven off from the solution in the generator-absorber, the shifting of the mass caused by the passage of the vapor to the condenser-evaporator shifts the rocking-frame to raise the generator-absorber and lower the condenser-evaporator, also discontinuing the flow of cooling water over the condenser-evaporator and causing it to flow over the generator-absorber to cool the same. In the second phase, the resulting decrease in pressure causes revaporization of the refrigerant liquid (ammonia with a negligible quantity of water), the vapor passing back to the generator-absorber to be absorbed in the solu tion therein contained, while the latent heat of vaporization of the refrigerant is sup plied from the surrounding atmosphere in the cold chamber.

Since the gas generated within the generator-absorber is lighter than the solution and rises, an exhaust pipe 68 is connected near the top of the tank 19 to carry off the generated vapor. To effect efficient absorption of the returning vapor, however, it must be introduced below the level of the solution, which would not occur if it were allowed to return through the exhaust pipe 68. There is therefore provided an absorption pipe 69 which terminates below the level of the liquid within the absorber 19, so that returning vapor bubbles up through the liquid and is absorbed.

Means must therefore be supplied to allow vapor to pass freely from the exhaust pipe 68 to the condenser-evaporator, but to pre vent returning vapor from passing through said pipe. In previously known refrigerat- /ing apparatus of the intermittent-absorption type various mechanical valves have been employed, but without satisfactorily solving the problem. A trap filled with liquid to a definite'height, through which the exhaust vapor bubbles on its way to the condenser, has also been employed; but this arrangement has many disadvantages, such as causing surging of the trap liquid into the condenser pipe.

There is therefore provided by this invention a closed chamber or-trap 70 connected at the bottom of its left-hand end by a pipe 71 with an L-shaped vessel or receptacle 72 near the lower corner of which pipe 71 terminates. All the pipes composing the refrigerant circulation system which conduct the refrigerant between the generator-absorber and the condenser-evaporator during the two phases of the complete cycle of operation open into trap 70 and certain of them will have their ends sealed or open in accordance with the osition of the rocking-frame 12. To sea such pipes at the proper time, vessel 72 contains a suitable quantity of heavy liquid, such as mercury, having a high boiling point and unattacked by boiling refrigerant. The mercury passes back and forth between trap 70 and vessel 72 in accordance with the pressure within the refrigerating a paratus. Thus, when the rocking-frame irst rocks to the left at the beginning of the first phase of refrigeration and heat is applied to the generator-l absorber drurn 19, the pressure within the system is'raised so as to forcethe mercury through pipe 71 into vessel 72 where it collects at the lefthand end, as indicated by the dotted lines in Fig. 1. The curvature of the pipe 71 is such as to provide a rise` or acclivity, shown in dotted lines, thereby forming a barrier to obstruct the flow of mercury under gravity. The level of mer` cury will not rise high enough to seal the lower end of ipe'71, so that the pressure within vessel 2 is the same as throughout the remainder of the apparatus.

At the end of the first phase of the operating cycle, when the rocking-frame rocks to the position shown in Fig. .2, the mercury collects about the lower end of pipe 71 and seals up the vapor at the high pressure then existing in vessel 72. Upon the ap.

plication of the cooling medium to the generator-absorber drum 19, lthe pressure within the apparatus asa whole is lowered so that the high pressure vapors locked within vessel 72 force the mercury 'up through pipe 71 into trap 70 where i't colfiects at the right-hand end of the trap to seal theends of pipes 68 and 28 throughout said second phase. It will thus be seen that in preparing a refrigerating apparatus for shipment it is merely necessary to carry on the first phase of refrigeration long enough to drive the mercury into vessel 72, and, thereafter, during shipment, to retain the rockingframe in this position. When this has been done, no rise in pressure in vessel 72 can -force the mercury up into vessel 70, as the mercury is clear of the end ci? pipe 71 no matter on which side the app..:atus as a whole is moved during shipment. y

In preparing the assembled refrigerating apparatus at the factory to perform its operating functions, the system is lirst exhausted of air through a tube shown at 73. The solution of aqua-ammonia or other refrigerant is introduced through this tube. A 50% solution of ammonia is suitable and at atmospheric temperature it has a pressure of about 20 pounds per square inch, and enough is used to nearly fill the generatorabsorber. The apparatus is lthen purged of any foreign gases, the mercur introduced through the tube 73, and ipe 3 is hermetically sealed as by a meta plug which may be soldered in place. As the generation of ammonia gas progresses, the weight of the generator (or left-hand) side of the system decreases and the condensed refrigerant in the tubes 22 gradually increases the weight of the other (or right-hand) side of the system, ..until, at the time that the desired amount of ammonia gas has been driven olf from the solution in the generator, the distribution of the weight of the system may be adjusted by means of lead shot or other wise so that the shifting of weight of amdensing position an the apparatus is ready vfor shipment.

When the apparatus is to be installed for use, the rocking-frame is unclamped so as to rock freely, and, since some of the refrigeran't fluid may have passed over to the condenser-evaporator durin shipment, it is well to move the apparatus rom its generating to its refrigerating position several times. While the apparatus is in the refrigerating position, as shown in 2, any

liquid in the condenser-evaporator will be' .collected at the header 26 as has been described, while upon movement to generating position the liquid so collected will flow through pipe 28 into chamber 70, from which it will ow through pipe 69 into the generator-absorber.

Owing tothe presence of the refrigerant solution in the generator-absorber, the lefthand side of the rocking-frame over balances the right-hand side, and the apparatus is in' the position illustrated in Fig. 1. As the water level in container 34 rises, it elevates float 38 until the mercury 42 contacts with yrods 66 to complete the circuit previously traced for the electricl stove which heats the generator-absorber. As the temperature within drum 19 is raised, ammonia vapor is generated from the solution and passes through exhaust pipe 68. (part of which is surrounded by water-jacket 51, as has been described) into closed chamber 70. From this chamber the vapor passes through pipes 28 and 74 to the header 26 of the condenserevaporator, whence the vapor is discharged into tubes 22. Owing to the gradually increasing pressure in the tubes and the flow of cooling Water from ipes 49, the ammonia gas is aduall coole and liquefied.

Whi e the ex aust pipe 68 is located at the opposite end of drum 19 from the stove 57 to prevent surging of the solution into said exhaust ipe, some water vapor will, nevertheless, e carried with the generated ammonia vapor; but a large part of this water vapor will be condensed while passing throu h water-jacket 5l and will flow back into t e generator by gravity. As the generation o f ammonia gas progresses, the

Weight of the generator (or left-hand) side of the system decreases and the condensed .refrigerant in the tubes 22 gradually increases the Weight of the other (or righthand) side of the system until the washer 12c of the rocking-frame engages and rests against its annular seat 10, thus ending the first or generating phase of the cycle.

At the commencement of the second phase of the cycle, the apparatus is in the position shown in Fig. 2, the cover 25 of the lcondenser-evaporator being substantially horizontal or sloping slightly toward the right. The cooling water stored in reservoir 48 now runs out through pipes 49 and drains through a number of slots adjacent header 26 between certain of the abutting tubes 22. Under each slot 75 there is a diagonally-sloping metal finger 76 down which the water coming through its slot 75 runs' to ll a cup 77 .into which the linger 76 dips at this time. As shown in dotted lines in Fig. 3, four such cups 77 may be conveniently cast on a bracket 78 iixed to the end wall of a box 79 ositioned under the condenser-evaporator. racket 78 also carries a smaller cup 80 out of thermal contact with the bracket. A stud 81 depending from the bottom of header 26 may enter the cup 8O. The volume of reservoir 48 is large enough that the water between the top and central pipes 49 may just fill small cup 80 by assing through a slot 82 (Fig. 3) and tric ling down header 26 and stud 81. The water flowing through the four remaining pipes 49 intocups 77 fills these cups. Any overflow, however, will run down to the lefthand rear corner of box 79 which is drained by a pipe 83 dipping into the water in sump 53. If desired, the overflow may be used to fill cup 80.

The cooling water now flowing through pipe 32 and water jacket 55 lowers the temperature and consequently the pressure within the generator-absorber, thereby causing the liquid refrigerant in tubes 22 and header 26 to again vaporize and pass back through pipe 74, chamber 70 and absorb-ing pipe 69 into the solution in the drum 19 where the ammonia vapor is again absorbed.

The mercury seal over the end of pipe 28 prevents any syphoning of liquid refrigerant from header 26 and thereby materially increases the efficiency of the apparatus, since itis only the vaporization of liquid refrigerant which removes heat from the surrounding atmosphere. The mercury seal also closes pipe 68 and forces all the vapor returning to the drum 19 to pass through pipe 69 to be absorbed, while, if it were allowed to pass through pipe 68, it would not be rapidly absorbed but would allow an equalization of pressure throughout the system, while there -was still liquid refrigerant within the condenser-evaporator.

The evaporation of the liquid refrigerant within the condenser-evaporator absorbs heat which can only be supplied from within the evaporator compartment 3. The air immediately surrounding the condensenevaporator thus becomes very cold, and owing to its increased density, passes downwardly around a bathe-plate 84, over the left-hand wall of box 79 `(which is cut away for this purpose) and through a number of apertures 85 in the lining of the condenser-evaporator compartment to the bottom or storage chambers S, all as indicated by the solid arrows in Fig. 2. The warm air at the top of storage chamber S passes up preferably through a conduit 86 at the rear of the cabinet, as indicated by the dotted arrows in Figs. 2 and 9, and being cooled by contact with the evaporator descends as just described. Thus the entire contents of chamber S are cooled by convection. In order to increase the conducting surface of the evaporator, metal fins 87 may be secured to the header 26, as shown. BaHie-plate 84 and box 79 may be made of heat insulating material such as libre-board or the like, so that the heat given off during the condensing of the refrigerant in the condenser evaporator will not be radiated to the chamber S but will be carried off by the cooling water flo-wing through pipe 50.

When the condensing stage is carried on in the chamber 3, the parts become quite warm, and it is desirable to prevent thermal communication with the food chamber. This is accomplished by the arrangement shown in f, Fig. 9. The heated air is ableto rise to the denser-evaporator will freeze the water contained in the cups 77 and 80. It usually freezes the water in the cup 8O rst and thereby locks the vertical stud 8l in position so that the condenser evaporator is held in its lower position. Continued lowering of the temperature will freeze the water in the cups 77 locking the diagonal fingers in the ice block so formed. Thus, although the returning refrigerant absorbed in the generator-evaporator increases the weight of the left-hand side of the apparatus and tends to rock the supporting frame to raise the con denser-evaporator (so as to recommence the first or generating phase of the cycle of operation), such movement of the apparatus cannot occur until after all the refrigerant has evaporated and sufficient external heat When, in consequence of the depletion of the refrigerant in the evaporator, the evaporator temperature rises above the freezing point of water, and the'teinperature ofthe adjacent heat-conducting metal parts is correspondingly raised; so that the ice blocks are loosened from cups 77 first, cup 80 being heat-insulated and, as the' temperature of thef evaporator -rises, the ice locks are also loosened from the diagonal lingers 76. Later the vertical stud 81 is released from the ice in cup 8O permitting the rocking-frame to raise the evaporator, the diagonal fingers lifting the loosened ice blocks out of the cups 77, whereupon the blocks slide down such fingers and fall, as indicated in dotted lines in Fig. 1, upon the sloping bottom of box 79. The blocks of ice 88 slide to the position shown in full lines in Fig. 1 where they rest on a heat insulating floor covering 89 of cork or the like until they are removed, theifront side of box 79 being cut away, as at 90, to permit such removal.

When the apparatus rocks to its generating position, there may remain in the condenser-evaporator a small amount of liquid consisting of condensed water vapor boiled over from the generator-absorber and containing in solution liquid ammonia; but such liquid, when present, will be in the header 26, whence it will. flow by gravity through pipe 28, chamber and pipe 69 back into the generator-absorber.

If for any reason during the heating phase the condensin comel full of liqui refrigerant without rocking the machine to start the refri erating phase, thereby tending to cause a angerously high pressurel within the system, the refrigerant liquid would overfiow from the upper ends of tubes 22 into header 26, whence it would flow as just described back to the generator-absorber. vapor is generated in the generator-absorber and passes 'into the condenser-evaporator to be liquefied, an equivalent amount of the liquid overfiows into theheader and flows back into the lower part of the generatorabsorber. Thus a condition-of equilibrium would soon be reached, under which a stream of vapor leaves the top of the generator-absorber, while its place is being constantly supplied by an equivalent stream of liquid flowing back into the bottom lof said generator-absorber. Although high pressure will attend the fillin of the condenser-evaporator with liquid, this overflow arrangement places a definite limit to the high pressure.

In order to render the refrigerating apparatus absolutely proof against explosion, in case the float switch in tank 33 or any reason fails to function to shut off the current in case of failure 'of thejcooling metubes 22 should be` As additional dium, or in case drain pipe 28 fails to carry off liquid ammonia sufiiciently fast, or if for any other reason an unsafe pressure develops within the refrigeratin apparatus, there is most desirably provi ed a safety blowout which, as here shown, (Fig. 10) comprises a tube 91, having one end opening into the upper rear wall of drum 19,

Idisk should not blow out upon the occurrence of every abnormal pressure, but only when the pressure reaches a predetermined point any increase above which would produce dangerous stresses within the refriverating apparatus. The diameter of the iiole in cap 92 is made of suchl an area that,

should the pressure rupture disk 94, they vapor contained in the apparatus would be exhausted vthrough tube 91 faster than it can be generated. The cooling water flowing through sum i 53 is able tovabsorb the fumes. Thus no 'liarmful results would follow the operation out of the safety blowout. To prevent leakage of gas from the chamber 4 to the room, a pipe 95 is shown which may be connected to the outdoors, or to a flue or any suitable Ventilating device. To again start operation, it is only necessary to replace the ruptured disk with a new one.

While the structure described shows a single container which may function as both condenser and as evaporator, it is possible to use separate containers, one to operate as a condenser, and the other as evaporator, a siphon or other means and suitable traps being employed to control the flow of refri erant.

, at I claim is:

1. Inl a rocking refrigeration-apparatus, the combination of two juxtaposed open-top receptaclesl carried thereby to rock to and fro between two extreme positions, deliverypipes for leading a cooling-li uid from said receptacles respectively to di erent portions of the apparatus, a supply-pipe for normally supplying such cooling-liquid selectively to one or the other ofsaid receptacles according to the positionthereof, and means whereby so long as the liquid-pressure in said supply-pipe is below a predetermined minimum the cooling-liquid will be prevented from reaching a certain o-ne of the receptacles yet will be free to reach the other regardless of the position occupied by said receptacles.

2. In a rocking refrigeration-apparatus, the combination of an open-top receptacle carried thereby to rock to and fro between two extreme positions, said receptacle being divided into an inner and an outer compa-rtment by a vertical partition one part of which is in the plane of such rocking and the remaining part is in a transverse plane, said inner compartment being located in the angle between said parts, delivery-pipes leading a cooling-liquid from said compartments respectively to different portions of the apparatus` and a supply-pipe for delivering such cooling-medium to said receptacle in a direction transverse to said plane of its rocking, whereby and so long as the liquidpressure in said supply-pipe is not below a predetermined minimum the cooling-liquid will be supplied selectively. to one o-r the other of said compartments according to the position thereof, and whereby so long as said liquid-pressure is below said minimum the cooling-medium will be prevented from reaching said inner compartment yet will remain free toreach the other regardless of the position thereof. A

3. In a refrigerating apparatus of the intermittent absorption type, two rocking refrigerant containers, an outlet-pipe atlording a passageway trom one of said containers to the other, an interposed chamber torming part of said passage-way and arranged to rock with said containers, a return-pipe affording a passage-way connecting said containers and having a mouth opening within said chamber, and a liquid within the chamber serving to seal and unseal said mouth in accordance with the position of the containers, a vessel for said liquid arranged to move with said chamber, and a pipe interconnecting the vesesl and chamber through which said liquid may pass from one'to the other as required.

- 4. In a retrigerating apparatus of the intermittent absorption type, two rocking refrigerant containers, an outlet-pipe aii'ording a passageway from one of said containers to the other, an interposed chamber torming part of in said passage-way and arranged to rock with said containers, areturn-pipe affording apassage-way connecting said co-ntainers and having a mouth opening within said chamber, and a liquid within the chamber serving to seal and unseal said mouth in accordance with the position of the containers, a vessel for said liquid arranged to move with said chamber, and a pipe interconnecting the Vessel and chamber through which said liquid may pass from one to the other as required, the lastnamed pipe leading from the floor of the chamber to near the ioor of the vessel.

5. In a refrigerating apparatus of the 1ntermittent absorption type, two rocking .refrigerant containers, an outlet-pipe atfordlng a passageway from one of said containers to the other, an interposed chamber forming part of said passage-way and arranged to rock with said containers, a return-pipe atfording a passage-way connecting said containers and having a mouth opening within said chamber, and a liquid within the chamber serving to seal and unseal said mouth in accordance with the posit-ion of the containers, a vessel for said liquid arranged to move with said chamber, and a pipe affording communication between the vessel and chamber through which said liquid may pass from one to the other as required, such movement of the liquid being caused from time to time by a difference of pressure within said chamber and vessel.

6. In a refrigerating apparatus of the intermittent absorption type, two rocking refrigerant containers, an outlet-pipe affording a passageway from one ot said containers to the other, an interposed chamber forming part of said passage-way and arranged to rock with said containers, a return-pipe affording a passage-way connecting said containers and having a mouth opening withinl said chamber, and a liquid within the chamber serving to seal and unseal said mouth inaccordance with the position of the containers, a vessel for said liquid arranged to move with said chamber, and a pipe interconnecting the vessel and chamber through which said liquid may 'pass from one to the other as required, such movement of the liquid being caused from time to time by a difference of pressure within said chamber and vessel and the relatively high pressure in the vessel being temporarily trapped therein by the liquid. Y

7. The combination with a refrigerating apparatus having arocking evaporator, of one or more stationary cups, one or more projections carried by the evaporator and adapted to dipl into said cups and become frozen to a liquid therein when said liquid freezes while the evaporator is in one position and to remove from the cups the ice blocks thus formed when the evaporator rocks to its other position.

8. The combination with a refrigerationapparatus having an evaporator rocking in vertical plane on a pivot, ot a stationary cup, a stud depending vertically from said evaporator and adapted to enter said cup and become frozen to a liquid therein when said liquid freezes while the evaporator is in its lowered position, an additional stationary cup having a diagonal wall on the side towards where said evaporator is pivoted, and a finger depending from said evaporator in a diagonal direction towards that same side and adapted to enter the lastnamed cup and become frozen to a liquid therein when said liquid freezes while the evaporator is in said lowered position and to remove the resultant ice-block from the last-named cup when the evaporator rocks to its elevated position.

9. In a refrigerating apparatus of the intermittent absorption type, the combination of two intercommunicating refrigerant containers, a heater for one of said containers, means for supplying a cooling, liquid for one of said containers, and means for regulating the supply of said liquid having provisions for controlling the operation of the heater.

lO. In a refrigerating apparatus of the intermittent absorption type, the combination of two intercommunicating refrigerant containers, a heater for one of said containers, means for supplying a cooling liquid for one of said containers, and means for regulating the' supply of said liquid including a float-operated valve, said float having associated therewith provisions for controlling the operation of said heater. v

1l. A refrigerating apparatus of the intermittent absorption type comprising a rocking-frame carrying on. its opposite arms two containers constituting respectively a generator-absorber and a condenser-evaporator, a chamber, a pipe affording a gas passage from the top of the generator-absorber into the chamber, a pipe affording a liquid-drain from the chamber into the lgenerator-absorber, piping affording two passages connecting the chamber and the condenser-evaporator, and a mass of mercury in the chamber which when the chamber is in a pre-determined position closes the first-mentioned passage and one of the latter-mentioned passages.

12. A refrigerating apparatus of the intermittent absorption type comprising a rocking-frame carrying on its opposite arms two containers each dually fuctioning, the one a generator-absorber and the other a condenser-evaporator, said generator-absorber and condenser-evaporator being interconnected in an operative refrigerating cycle, the interconnections being bodily movable with the rocking-frame and including a chamber and piping affording two communications with the generator-absorber and two communications with the condenser-evaporator, and means to render one generatorabsorber communication and one condenserevaporator communication non-functioning when the rocking-frame is in one position.

13. A refrigerating apparatus having a rocking-frame fulcrumed on a horizontal pivot and carrying a condenser-evaporator, which is movable with said frame between an upper or condensing position and a lower or evaporating position, a cup having on the side towards said pivot an outwardly-flarin wall, said cup being suitably located to receive water for freezing, means for fillin the cup each time the condenser-evaporator g tion during the generating is lowered, a member depending from the condenser-evaporator and downwardly inclined towards the center line of the apparatus where' said pivot is located, said member occupying a diagonal position in said cup when the condenser-evaporator is in its lower position and extending above said flaring wall and towards said center line when the condenser-evaporator `is in theJ upper position, whereby the reduced temperature attending said lower and condensing position reduces the water in said cup to an ice-block, and the subsequent rise of temperature loosens said ice-block from said cup and member, and the resultant rising of the condenser-evaporator with said member ejects the ice-block fromv the cup.

14. In a rocking refrigeration-apparatus ofthe intermittent absorption type, the combination of a rocking frame, a generator-absorber and a condenser-evaporator carried on the opposite arms thereof, suitable means for producing the successive stages of refrigerating, including means for applying heat to the generator-absorber, and means for applying cooling-water alternately to the generator-absorber and the condenser-evaporator, and the combination with the foregoing of ya water-tank for supplying said cooling-water, a float for normally maintaining a constant water-level therein, and means whereby the falling of said water-level below a predetermined position will prevent said 'applying of heat. l5. In a refrigerating-apparatus of the herein-described intermittent absorption type comprising a rocking-frame which fulcrums on a horizontal pivot and carries on its opposite arms a generator-absorber Iand a condenser-evaporator respectively and which has a return-conduit from said condenser-evaporator to the bottom of said generator-absorber, the combination of a mercury-trap mounted on said rockingframe and comprising two chambers which lave one end nearer land the opposite end farther from said pivot, the main trapchamber having a substantially-horizontal floor and being at alltimes in free communication with the top of said generatorabsorber, a vapor-pipe leading to said condenser-evaporator from =a downturned mouth located near the floor of said nearer end of said main chamber, a siphoning-pipe leading from the further end of the said main chamber and passing over a rise to a downturned mouth located near the floor of said nearer end of the supplemental trapchamber, and a supply of mercury within said trap, whereby while the mouth of said vapor-pipe is in its relatively-highest posiand condensing phase the excess of pressure in said main g chamber maintains all the mercury within the supplemental chamber and leaves said mouth free, and while said mouth is in its relatively-lowest position during the evaporation and absorbing phase. the reduced pressure in said main chamber has sucked in some of the mercury which seals said mouth.

16. In a refrigerating-apparatus of the herein described intermittent absorption type comprising a'rocking-rame which fulcrums on a horizontal pivot and carries on its opposite arms a generator-absorber and a condenser-evaporator respectively and which has a return-conduit from said condenser-evaporator to the bottom oit said generator-absorber, the combination of a mercury-trap mounted on said rockingrame and comprising two chambers which have one end nearer and the opposite ,end further from said pivot, the main trapchamber having a substantially-horizontal floor and being at all times in free communication with the top.A of said generatorabsorber, a -vapor-pipe leading to said condenser-evaporator from a downturned mouth located nearl the floor of said nearer end of said main chamber, a siphoningpipe leading from the further end of the bottom of said main chamber and passing over a rise to a downturned mouth located near the oor of said nearer end of the supplemental trap-chambenand a supply of mercury within said trap.

17. In a refrigerating-apparatus of the herein-described intermittent absorption type in which an enclosure is divided by an apertured artition into a working-chamber and a col -storage chamber, and which apparatus comprises a rocking-frame fulcrumed on a horizontal pivot located neaIl the aperture in said partition with one arm Aof said frame located in said workingchamber and supporting therein a generatorabsorber while the opposite arm extends through said aperture and supports in said storage-chamber a condenser-evaporator which is movable with said arm into an upper position where it receives the vapors generated by the then-lowered generator-absorber and likewise undergoes an external application of cooling-water which condenses said vapors, said condenser-evaporator being also movable with said arm into a lowered position where it evaporates its condensed contents and thereby chills the interior of said storage-chamber while delivering its re-evaporated contents to said generator-absorber, the combination with said condenser-evaporator of a member depending therefrom and inclined towards said partition, a cup located in said storagechamber in position to receive said depending member and be lled with some of said cooling-water each time the condenserevaporator is lowered, said cup having on the side nearer said partition an outwardlyflaring wall, whereby the chilling which attends the evaporating-stage reduces the contents of said cup to an ice-block and the ensuing rise of temperature loosens said iceblock from said cup and member so that the resultant rising of the condenser-evaporator and member ejects the ice-block.

18. In a refrigerating-apparatus of the intermittent absorption type which comprises a condenser-evaporator movable upon. a pivoted arm from`an upper and condensing position where it is subjected to coolingwater down to a lower and evaporating position, and vice versa, means for producing ice-blocks which comprise a plurality of members depending from said arm adjacent said condenser-evaporator and inclined towards the pivoted end of said arm, a plurality of cups located in position to receive said members respectively and be filled with said cooling-water each time said arm is lowered, each cup having an outwardly-fiaring wall in the side towards said pivotal end of the arm, whereby the reduced temperature attending the evaporation-stage reduces the contents of said cups to ice-blocks, and the subsequent rise of temperature loosens the ice-blocks from the cups and members, and the ensuing rise of said arm and members ejeets the ice-blocks from the cups.

19. In a refrigerating-apparatus of the intermittent absorption type which comprises a condenser-evaporator movable upon a pivoted arm from an upper and condensing position where it is subjected to coolingwater down to a lowered and evaporating position, and vice versa, means for producing an ice-block which comprise a member depending from said arm adjacent said condenser-evaporator and inclined towards the pivotal end of said arm, a cup located in position to receive said member and be filled with said cooling-water each time said arm is lowered, said cup having an outwardlyflaring wall on the side towards said pivotal end of the arm.

20. In a refrigerating-apparatus of the intermittent absorptionl type described, which comprises a rocking-:trame fulcrumed on a horizontal pivot and carrying on one arm a generator-absorber and on the opposite arm a condenser-evaporator, andwhich has a heating-system for said generator-absorber and a water-cooling system for the same and also for said condenser-evaporator, and in combination with the foregoing apparatus, a device directly controlling the supply for said heating-system, a second device directly controlling the supply for said water-cooling system, and a oat having a fusible plug for actuating the devices aforesaid, whereby the lowering of the float below its normal level admits more water and the fusing of said plug by abnormal temperature of the water promptly sinks the float and shuts-off the supply for the heating-system.

21. In a refrigerating-ap-paratus, a generator-absorber and a condenser-evaporator supported on opposite arms of a rockingframe, a trap supported by said frame to rock therewith, an exhaust-pipe leadingl from the upper portion of said generator-absorber to said trap, another pipe leading from said trap to said condenser-evaporator, a returnpassage leading from said condenser-evaporator into the lower portion of said generator-absorber, and a liquid within said trap serving to seal said exhaust-pipe while said frame is in one position and moved by gravity to open said exhaust-pipe when said frame has rocked into the other position.

22. In a refrigerating-apparatus, a storage-chamber having heat-insulating walls, a rocking-frame extended through an aperture in one of said walls, a generator-absorber supported on one arm of said frame outside the chamber, a condenser-evaporator supported on the other arm of said frame within the chamber, said generator-absorber and condenser-evaporator being connected in an operative cycle, and means carried by said frame for sealing said aperture to prevent the flow of heat into said chamber while said condenser-evaporator is in evaporating position.

23. In a refrigerating-apparatus, having two inter-communicating enclosed containers mounted on opposite arms of a rockingframe, a refrigerant solution'in the first container, heating-means operable while the rocking-frame is in one position for driving the refrigerant from said solution into the second container, cooling-means operable simultaneously7 for condensing said refrigerant withinsaid second container, the passage of a quantity of' refrigerant between the containers operating to rock the frame and ythereby lower the second container and stop the operation of said 4heating and cooling means, means responsive to the cessation of the heating-means Awhich operates to revolatilize the refrigerant in the second container and to draw the vapor into the i'irst container, and in combination therewith means responsive to the cold produced by said revolatilization for retaining the second container in its lowered position after said refrigerant has passed to said first container, said last-mentioned means being rendered inoperative responsive to the absorption of a predetermined quantity of external heat.

24. In a refrigerating-apparatus of the intermittent absorption type, the combination of two enclosed containers mounted on opposite arms of a vertically reciprocable rocking-frame and intercommunicating with one another and containing a refrigerating- Huid, means for heating one of said containers to vaporize a portion of said Huid and thereby drive the resultant Vapor into the second container, means for cooling said second container to liquefy said vapor, means for cooling said first container, the passage of said vapor to said second container tending to cause said frame to rock and thereby lower said second container, the said rocking-movement simultaneously discontinuing the operation of the heatingmeans and of the cooling-means aforesaidk and applying said cooling means to said first container whereby the internal pressure is reduced and liquid refrigerant within said second container is re-vaporized and returned into the first-named container for absorption, thereby tending to roclr said frame back to its former position and simultaneously re-apply said lieating-means and the first-named cooling-means, and additional means responsive to excessive cold produced by said re-vaporization for retaining said second container in its lowered position after said vapor has returned and until it is released by the accumulation of external heat.

25. In a refrigerating-apparatus of the intermittent absorption type, the combination of two enclosed containers mounted on opposite arms of a vertically reciprocable rocking-frame and intercommunicating with one another and containing an absorbent liquid and a volatile refrigerant, means for heating one of said containers to vaporize said refrigerant and thereby drive the resultant vapor into the second container, means for cooling said second container to liquefy said vapor, cooling-means for the first container, the passage of said vapor to said second container tending to cause said frame to rock and thereby lower said s econd container, said; rocking-movement-discoiitinuing the operation of the heating and the cooling-means aforesaid and applying said cooling-means to said first container whereby the internal pressure is reduced and liquid refrigerant within said second container is re-vaporized and returned into the first-named container, thereby tending to rock said frame back to itsl former p osition to re-apply said heating and coolingmeans aforesaid, and means comprising a stationary liquid-containing cup and a member carried by the second container and arranged to enter said liquid when said container is lowered, whereby the re-vaporization aforesaid freezes the liquid in said cup to lock said container in its lowered position.

26. In a refrigerating-apparatus of'the intermittent absorption type, the combination of a heat-insulating casing enclosing a chamber, a two-armed rocking-frame having one arm extending into and normally swingable vertically within said chamberna container mounted on the outer arm of said rocking-frame as a generator-absorber, means for heating said container while the latter is in its lowered position, means for discontinuing said heating when said container is raised, means for cooling' said container while the latter is in its elevated position, means for discontinuing said cooling when the container is lowered, a second container swingable within said chamber upon the inner arm of said rocking-frame as a condenser-evaporator, means for cooling Said second container while the latter is in its elevated position, means for discontinuingsaid cooling when said second container is lowered, an outgoing conduit from the generator-absorber to the condenser-evaporator, an automatic one-direction-only mercury-valve comprised in said conduit, and a second conduit affording a return-passageway from said condenser-evaporator around said valve and to said generator-absorber, said containers and conduits being adapted to receive a 'refrigerant solution.

27. In a refrigerating-apparatus of the intermittent absorption type, the combination of a heat-insulating casing enclosing a chamber, a two-armed rocking-frame havin one arm extending into and normally swingable vertically within said chamber, a container mounted on the outer arm of said rocking-frame as a generator-absorber, means for heating said container while the latter is in its lowered position, means for discontinuing said heating when said container is raised, means for cooling said container while the latter is in its elevated position, means for discontinuing said cooling when said container is lowered, a second container swingable within said chamber upon the inner arm of said rocking-frame as a condenser-evaporator, means for cooling said second container` while the latter is in its elevated position, means for discontinuing said cooling when said second container is lowered, a conduit affording a gas-passage from the top of the first container into the 'second container, piping aiiording a returnpassageway from an `Intermediate portion of said conduit into the lower part of said first container, and an independent conduit affording a passageway from a remote portion of the second container to said piping.

28. In a refrigerating-apparatus of the intermittent absorption type, the combination comprising a generator-absorber and a condenser-evaporator mounted in operative relation upon the opposite arms of a rocking-frame and containing a refrigerant solution, a heating-device such as an electric` stove and a water-jacket for said generatorabsorber and also an automatic one-direction-only mercury-valve controlling the communication between said generator-absorber and said condenser-evaporator, said device and jacket .and valve being carried on said frame in connection with said generator-ab sorber, means operable when the rockingframe is in one position for connecting said device in circuit to thereby heat the contents of said generator-absorber, means operati-ng simultaneously therewith for applying a cooling-medium to said condenserevaporator, and means operating in alternation-with the two means aforesaid tor applying a cooling-medium to said generator-absorber, the sequence of operation oi the three means aforesaid being brought about by the tilting of said frame auton'iatically brought about by the shift of refrigerant due to the passage of the vaporizcd refrigerant.

29. In a refrigerating-apparatus ot the intermittent absorption type, the combination comprising a generator-absorbcr and a condenser-evaporator mounted in operative relation upon the opposite arms of' a rocking-frame and containing a refrigerant solution, a heating-device carried on said frame for heating said generator-absorber when the rocking-frame is in one position, means operating simultaneously therewith for applying a cooling-medium to said condenserevaporator, means operating in alternation with the two means aforesaid for applying a cooling-medium to said generator-absorber, the sequence of operation of the three means aforesaid being brought about by the tilting of said frame, and a stud carried by said condenser-evaporator and adapted to enter a'stationary liquid-containing cup and become locked therein by the freezing of said liquid brought about by the re-vaporization of the contents of said condenser-evaporator.

30. In a refrigerating-apparatus of the intermittent absorption type, the combination comprising a cold or storage-chamber and an apparatus-chamber separate from one another by an apertured partition, a rocking-frame, one arm of which protrudes through said aperture, a generator-absorber and a condenser-evaporator mounted on the opposite arms of said rocking-frame in operative relation and containing a refrigerant solution, suitable devices actuated by the tilting of said frame to simultaneously apply heat to said generator-absorber and a cooling-medium to said condenser-evaporator and in alternation therewith to apply a cooling-medium to said generator-absorber. a liquid-containing cup mounted within said storage-chamber, and a stud carried by said condenser-evaporator and adapted to enter said cup and become frozen therein.

31. In a refrigerating-apparatus of the intermittent absorption type, the combination comprising a cold orstorage-chamber and an apparatus-chamber separated from one another by an apertured partition, a rocking-frame, one arm of which protrudes through said aperture, a generator-absorber and a condenser-evaporator mounted on the opposite arms of said rocking-frame in operative relation and containing a refrigerant solution, suitable devices actuated by the tilting of said frame to simultaneously apply heat to said generator-absorber and a cooling-medium to said condenser-evaporator and in alternation therewith to apply a cooling-medium to said generator-absorber, and a member carried by said rocking-frame and adapted to seal said aperture while said generator-absorber is being subjected to the cooling-medium aforesaid.

32. In a rocking refrigerating-apparatus of the intermittent absorption type, a checkvalve consisting of a chamber mounted to rock with said apparatus, an outlet-pipe protruded through the wall of said chamber and terminating above the floor thereof, an inlet-pipe protruded through the wall of said chamber and terminating with a mouth near the floor thereof, and a mass of mercury in said chamber which automatically operates to close and unclose saidv mouth according to the operative position into which said apparatus vis rocked.

33. In a rocking refrigerating-apparatus comprising a vertically-reciprocable member which occupies its lowered position durlng the phase of vaporization, the combination of a cup for containing a freezable liquid such as water, and a stud positioned on said member to be lowered into said -cup and be held there by the freezing of said liquid.

34. A refrigerating apparatus of the intermittent absorption type comprising a rocking-frame carrying on its opposite arms two contamers constituting respectively a generator-absorber and a condenser-evaporator, all parts of the condenser-evaporator being higher at all times than the generatorabsorber, and means associated with the containers and frame whereby a refrigerating cycle may be performed, the rocking of the frame being effected by the weight of the refrigerant which is in the operation of the apparatus transformed in the vapor state from one container to the other and the rocking ofthe frame in turn controlling the order of the stages of the cycle, said means including means for preventing therocking of the frame when the temperature adjacent the condenser-evaporator has been reduced below a predetermined temperature.

35. A refrigerating apparatus of the intermittent absorption type comprising a rocking-frame, a horizontal pivot therefor, a generator-absorber carried on one side of the pivot, a condenser-evaporator lcarried by the frame on the other side of the pivot, means associated with theV aforesaid to permit the carrying out of a refrigerating cycle, the inter-relation of parts being such that vapor can pass from the generator-absorber tqsthecondenser-evaporator and such that liquid can pass from the condenser-evaporator to the generator-absorber only when the generator-absorber is in its lower position, and means for holding the rocking-frame out of the latter position when the temperature of the air surrounding the condenserevaporator is below a predetermined point to thereby prevent such How of liquid.

36. In a refrigerating apparatus, a rocking-frame, a generator-absorber mounted on the rocking-frame movable therewith and adapted to contain a refrigerant fluid, an outlet at the top of the generator-absorber for vapor generated therein, a normally submerged inlet whereby returning vapors may be bubbled through the fluid, interconnections for conveying from the generatorabsorber to a condenser vapors for condensation therein and for returning cold vapors for re-absorption, an supported by and movable with the generator-absorber, and means whereby said heater is automatically energized upon lowering said generator and automatically de-energized upon raising' it.

37. In a refrigerating apparatus, a rocking-frame, a generator-absorber mounted on the rocking-frame, movable therewith and adapted to contain a refrigerant fluid, an outlet at the top of the generator-absorber for vapor generated therein, a normally submerged inlet whereby returning vapors may be bubbled through the fluid, interconnections for conveying vapors from the generator-absorber to a condenser for condensation therein and for returning cold vapors for vre-absorption, an electric heater bodily supported by and movable with the generator-absorber, and a circuit breaker automatically opened when the generator-absorber is raised.

38. In a refrigerating apparatus, a rocking-frame, a generator-absorber mounted on the rocking-frame, movable therewith and adapted to contain a refrigerant fluid, an outlet at the top of the generator-absorber for vapor generated therein, a normally submerged inlet whereI y returning vapors may be bubbled through the fluid, interconnections for conveying vapors from the generator-absorber to a condenser for condensation therein and for returning cold vapors for re-absorption, a rectifying device for chilling the vapors to cause water to condense and drain into the generatorabsorber, means responsive to rocking of the frame to force returning vapors through the submerged inlet, an electric heater bodily supported by and movable with the generator-absorber, and means whereby said heater is automatically energized upon lowering said generator and automatically de-energized upon raising it.

39. In a refrigerating-apparatus, a rocking-frame, a generator-absorber mounted electric heater bodilyl bodily supported by and movable With the generator-absorber, a cooler for the generator-absorber bodily movable with the rocking-frame, and means controlled by the rocking of the frame whereby the rocking of said frame into one extreme position energizes said heater and renders said cooler non-functioning, and the rocking of said frame into the opposite position de-energizes said heater and permits said cooler to function.

40. In a refrigerating apparatus, a condenser-evaporator comprising a plurality of tubes arranged side by side and always closed at one end and opening at the other end into a transverse header, the transverse ,header having a sloping bottom, a drain connected to the bottom of the header, an inlet ior each tube, and means for applying cooling medium to the outside of the tubes. l

41. In a refrigerating apparatus, a movably mounted condenser-evaporator, means affording a'passa'geway for supplying the condenser-evaporator with vapor from a generator-absorber for condensation and for returning vapor evaporated in the condenser-evaporator to the generator-absorber for absorption, said means affording a branch passageway through which liquid may iow from the condenser-evaporator, a valve leaving said branch open only when the condenser-evaporatorV is in a predetermined position, means for supplying cooling medium to the condenser-evaporator when the condenser-evaporator is in said predetermined position, and means for holding the condenser-evaporator out of said n predetermined position while the surrounding temperature is below a predetermined temperature.

42. In a refrigerating apparatus, a condenser-evaporator comprlsing a plurality of tubes arranged side by side closed at one end and opening at the other end into a transverse header, the transverse header having a sloping bottom, and a drain connected to the bottom of the header.

43. A refrigerating apparatus of the intermittent absorption type, comprising a rocking-frame carrying on its opposite arms two containers each dually functioning, the one constituting a generator-absorber, and the other a condenser-evaporator, all parts of the condenser-evaporator being higher at all times than the generator-absorber, means for applying cooling water to the condenser-evaporator when it is in one position, and a conduit bodily movable with the frame for draining the cooling water to carry it above the generator-absorber.

44. A refrigerating apparatus of the intermittent absorption type, comprising a rocking-frame carrying on its opposite arms two containers constituting respectively aA generator-absorber and a condenser-evaporater, all parts of the condenser-evaporator being higher at all times than the generatorabsorber, means for applying cooling water to the condenser-evaporator when it is in one position, a conduit for draining the cooling water to carry it above the generator-absorber, and a pipe extending from the lower interior of the generator-absorber upwardly to the interior of the condenserevaporator, said pipe passing through the conduit whereby vapors passing upwardly may be rectified land condensate drained into the generator-absorber.

. 45. In a refrigerating apparatus, a chamber having heat-insulating walls, a rockingframe extended through an aperture in one of said walls, a generator-absorber supported on one arm of said frame outside the chamber, a condenser-evaporator located within the chamber and mounted to swing vertically on the other arm of said frame, said generator-absorber and condenserevaporator being interconnected in an operative refrigerating cycle, all connections for transferring refrigerating medium into or out of the condenser-evaporator and for applying cooling medium to and removing it from the condenser-evaporator being bodily movable with the rocking-frame and passing throu h the aperture, and means carried by sai frame for sealing said aperture to prevent the iiow of heat into said chamber while said condenser-evaporator is in evaporating position.

46. In a refrigerating apparatus, a chamber having heat-insulating walls, a rockingframe extended through an aperture in one of said walls, a generator-absorber supported on one arm of said frame outside the chamber, a condenser-evaporator located within the chamber and mounted to swing vertically on the other arm of said frame, said generator-absorber and condenser-evaporator being interconnected in an operative refrigerating cycle, all connections for transferring refrigerating medium into or out of the condenser-evaporator and for applying cooling medium to and removing it from the condenser-eva orator being bodily movable with the rocking-frame and .passing through the aperture, means carried by said frame for sealing said aperture to prevent the flow of heat into said chamber wliile said condenserevaporator is in its lowered and evaporating position, and means for preventing the rising of the condenser-evaporator so long as the temperature in the storage chamber is below a predetermined temperature.

47., A refrigerating apparatus having. a rocking-frame,` means controlled by the rocking of the frame for controlling the sequence of the stages of the cycle, and a device for interrupting the rocking of the frame when the refrigerating apparatus has reduced the temperature to a predetermined temperature, said device comprising a liquid receptacle, a freezable liquid therein, and a member' carried on the rocking-frame in a position to enter the receptacle.

48. A refrigerating apparatus, having a rocking-frame, means controlled by the rocking of the frame for controlling the sequence of the stages of the cycle, and a device for interrupting the rocking of the frame when the refrigerating apparatus has reduced the temperature to a predetermined temperature, said device comprising a trap carried on the rocking-frame and adapted to alternately receive and deliver a quantity of liquid, a receptacle for the liquid released from the trap, and a member carried on the rocking-frame in a position to enter the receptacle.

49. In a refrigerating apparatus, a generator-absorber and a condenser-evaporator supported on opposite arms of a rockingframe and adapted to contain a refregerant fluid, means such as an electric stove for generatin vapor in said generator-absorber and there y driving said vapor into said condenser-evaporator to rock said frame, a power circuit for said stove, and means responsive to the rocking of said frame in one direction for interrupting said power circuit.

DAVID FORBES KEITH. 

